Shuttle astronaut taken off crew for ISS mission

(CNN) -- After an apparent falling out with NASA brass in Houston, astronaut Mark Lee has been removed from a space shuttle mission to the International Space Station next spring.

Lee has been assigned to "other duties for administrative reasons," said NASA spokesman Ed Campion. "He remains eligible for a future assignment."

Campion declined to characterize Lee's removal from the scheduled Atlantis mission as a disciplinary action, calling it an "internal astronaut office matter."

"It was intended to maintain the high level of professionalism necessary to insure the integrity of space flight," he said.

A NASA source indicated there had been a breakdown of communication between Lee and at least one of his superiors at the NASA's Johnson Space Center in Houston.

Mission Commander Ken Cockrell and the remainder of the crew were informed of the decision by the head of the Astronaut Office, Jim Wetherbee.

"They are all professionals and they will do their job," Campion said.

Mission will deliver lab to ISS

Scheduled to fly in May 2000, the mission Lee was training for will deliver a crucial component to the space station: the U.S. Laboratory that will be NASA's primary scientific platform on the orbiting outpost.

Lee was training to participate in a series of spacewalks to attach the Lab to the ISS.

He will be replaced by astronaut Bob Curbeam, who was in training for a spacewalk on the subsequent space station assembly mission. Curbeam's replacement has not been announced.

Lee married to fellow astronaut

Lee, 47, is a veteran of four shuttle missions. In September 1992, he and his wife became the first U.S. married couple to fly together in space.

Lee met astronaut Jan Davis during training for the mission and kept their marriage secret until just prior to launch. Since removing one or both of them at that late juncture would have adversely impacted the mission, NASA allowed them to fly together.

NASA has since instituted rules prohibiting married couples from flying on the same space missions -- "for the same reasons the Navy doesn't allow relatives on the same ship," Campion said.

Davis has left the astronaut corps and now works for NASA's Marshall Space Flight Center in her hometown of Huntsville, Alabama.

Removing an astronaut from a mission for disciplinary reasons is not unprecedented. Astronaut Dave Walker was dropped from a mission after inadvertently "buzzing" a commercial airliner. Robert "Hoot" Gibson was taken off a flight after participating in an air show in violation of NASA rules.